Plan Your Trip Times Picks

A Guide to Exploring the World Under

By DAVID E. PITT; DAVID E. PITT, a reporter on the metropolitan staff of The New York Times, has been diving for 10 years.

Published: July 9, 1989

DEJA VU is common among skiers who go scuba diving in the Caribbean: Despite the warmth, there is something oddly familiar about that first plunge into the blue-green water. Most will tell you that few things compare with the exhilaration of an early morning run through fresh-fallen powder; but one of them is the thrill of soaring, weightless and silent, over a coral reef alive with fish.

There are other similarities. Scuba diving tends to attract people of widely differing skills and tastes. Often, those just learning the sport settle for lesser experiences - uninteresting reefs and marginal water visibility, for instance - in return for comfort and a sense of security.

Determined veterans, on the other hand, will put up with just about anything - long boat rides, hard bunk beds and terrible food, to name a few possibilities - for the opportunity of diving a seldom-visited coral wall, or of swimming goggle-eyed past a school of pelagic sharks. It all depends on your enthusiasms, your daring and your inclination to rough it, not to mention your wanderlust - there are almost as many resorts that offer competent scuba diving and instruction as there are islands in the Caribbean.

At one pole is Grand Cayman Island, which has emerged in recent years as the scuba divers' answer to Aspen. Part of a British colony 500 miles south of Miami, Grand Cayman has scores of spectacular dive sites that begin in shallows accessible to any novice, along with first-class hotels, a variety of restaurants, and pulsating night life. It is nirvana for casual beginners and snorkelers alike, and very pleasant for those looking for a simple beach vacation.

Bonaire, 35 miles off the coast of Venezuela, is something else again. A tiny coral atoll in the Netherlands Antilles, it has long been a magnet for people who want to do little but dive - even at night, when the reefs take on a whole new identity under hand-held lights. There are, to be sure, places to go and things to do on Bonaire - but its chief draws remain its year-round perfect weather, crystalline water and coral walls, which are among the most unspoiled in the Caribbean.

For novices, the quality of instruction should be a paramount consideration in deciding where to go. Scuba diving is a safe sport, but it is not for the absent-minded. Carelessness can kill you, a theme instructors like to drum into their first-time students. It usually catches their attention.

Most of the major dive resorts around the Caribbean offer classes in scuba diving, and most are accredited by the major American teaching organizations, either the Professional Association of Diving Instructors (commonly called Padi), or N.A.U.I., the National Association of Underwater Instructors. While the better resorts generally offer strict, no-nonsense instruction, some diving teachers, through sheer dint of personality, inspire more confidence in novices than others. Finding the right one is often a matter of chance, helped along by intuition.

Instruction ranges from so-called resort courses, which teach basics, to full-scale ''open water'' regimens, which lead to full certification. Open-water instruction combines classroom and underwater lessons in such matters as diving physiology, equipment handling, life saving, navigation and marine biology.

One can dive without being certified, but certification documents -more familiarly known as C cards - bestow a certain measure of freedom. Once bearers convince the presiding dive master of their skills - a gantlet that must be run at every dive resort - they're usually allowed to dive without the close supervision automatically given those without certification. They can also purchase breathing equipment and refills for air tanks, a privilege ordinarily denied noncertified customers.

The resort course usually involves an afternoon, much of it commonly in a swimming pool; the open-water course takes closer to a full week to complete. (Many people save time by taking the classroom end of the open-water course at home, at a more leisurely pace, then complete the underwater segment on vacation.) One increasingly popular option among intermediate and advanced divers is to find a live-aboard, a dive boat that visits out-of-the-way spots on voyages that last a week or more.

Other elements to consider are water clarity and temperature. Since these are usually a function of the season and the weather, it's best to check carefully before you make reservations. Ordinarily, summer and fall are the best seasons everywhere in the Caribbean, barring hurricanes.

Another consideration is the condition of the reefs. Coral, the limestone formations produced by colonies of tiny marine organisms, is easily damaged, and the cumulative effects of being touched and accidentally brushed by passing divers can be devastating. Some resorts and Caribbean governments have instituted strict controls on anchoring practices and the number of divers that may visit reefs at a time. At some of the more popular spots, such as in parts of the Florida Keys and around Grand Cayman Island, the reefs are bruised and dying from too many visitors.